MINIMUM 25-YEAR OUTCOME OF STANDARD DISCECTOMY FOR LUMBAR DISC HERNIATION

Abstract

Aim of the present study was to investigate clinical outcomes and quality of life after standard discectomy for lumbar disc herniation on a minimum 25-year follow-up throughout validated tools. Between 1973 and 1979, a total of 343 patients underwent single or double level standard lumbar discectomy at the Orthopaedic Department of Naples Federico II University Hospital, Italy. Fifty patients died from causes unrelated to disc surgery. Out of the remnants, one hundred fifty-eight patients could be traced and contacted by mail (46.1% survey rate). All of them (100% response rate) completed and sent back three questionnaires: the official Italian version of the Short Form-36 Health Survey (SF-36), the Oswestry Disability Questionnaire, and a questionnaire ideated by the authors to evaluate the degree of satisfaction with surgery. Forty-two patients even accepted to undergo clinic examination. The study population consisted of 97 males and 61 females. The mean age at the time of surgery was 37.8 +/− 8.7 years (18–62), whereas on follow up it was 65.8 +/− 8.9 (44–89). The average follow up in the study group was 27 years (25–31). The eight SF-36 scales averaged 72.53 +/− 31.3 for physical functioning, 63.1 +/− 30.1 for bodily pain, 61.30 +/− 44.4 for role-physical, 54.57 +/− 22.2 for general health, 56.62 +/− 19.2 for vitality, 72.08 +/− 30 for social functioning, 67.56 +/− 41.4 for role-emotional, and 62.28 +/− 19 for mental health. The mean SF-36 physical composite score (PCS) and mental composite score (MCS) were 44.2 +/− 11.6 (17.3–64.5) and 45.7 +/− 9,9 (13.2–62.4), respectively. The mean Oswestry Disability Score was 16.67 +/− 22.82 (0–96). One hundred forty-two patients (89.9%) were satisfied with the results of surgery, whereas sixteen (10.1%) were dissatisfied. One hundred and one (89.2%) would have had the same operation again. Nineteen patients underwent recurrent back surgery, giving a reoperation rate of 12%. As for the objective findings, we noted slight improvement of motor disturbances, hyporeflexia, and radicular tension signs with respect to preoperative period. Lumbar alignment abnormalities and trunk mobility did not show significant changes. On multivariate analysis worst SF-36 PCS scores were associated with increasing age (P = 0.039), low educational level (P = 0.002), and reoperation (P = 0.008). Similar correlations were appreciated for the Oswestry Disability Score. Negative role of female gender (P = 0.012) in determining the score of SF-36 MCS was also detected. To the best of our knowledge, no patient-oriented evaluation of lumbar discectomy outcomes has been reported with a similar ultra-long-term follow-up. The minimum 25-year results obtained in the present study were satisfying for both general health and disability indicators. The general health scores were similar to age-adjusted normative values.